Suitability of different substrates for enriched mixed microbial cultures (MMCs) is of importance to the polyhydroxyalkanoate (PHA) fermentation using renewable carbon. In this study, three enriched MMCs were evaluated for their fermentation features and kinetics with different carbon sources (sodium acetate, glucose, or starch). The results showed that the highly specific bacterial community composition was developed depending on the applied carbon source. Correspondence analysis suggested that the genus affiliated in Gammaproteobacteria_unclassified was related to 3-hydroxybutyrate (HB) synthesis in acetate-fed MMC (relative abundance of 38%) and glucose-fed MMC (relative abundance of 76.7%), whereas Vibrio genus was related to 3-hydroxyvalerate (HV) production in glucose-fed MMC (relative abundance of 0.4%) and starch-fed MMC (relative abundance of 94.6%). The acetate-fed MMC could not use glucose and starch as fermentation carbon sources, showing the limitation of microbial species developed with the specific metabolic substrate. Glucose-fed MMC produced the highest PHA cell content of 64.2% cell dry weight when using sodium acetate as the fermentation carbon. Glucose-fed MMC showed wide resilience and adaptation to various carbon sources. When actual landfill leachate was used for fermentation by glucose-fed MMC, maximum PHA cell content of 45.5% cell dry weight and the PHA volumetric productivity of 0.265 g PHA/(L·h) were obtained. This study suggested carbon sources applied in the MMC enrichment stage had a significant influence on utilization of carbon in the fermentation stage.

不同底物对富集混合微生物培养物 (MMC) 的适用性对于使用可再生碳进行聚羟基脂肪酸酯 (PHA) 发酵非常重要。在这项研究中，评估了三种富集的MMC在不同碳源（乙酸钠、葡萄糖或淀粉）下的发酵特性和动力学。结果表明，高度特异性的细菌群落组成取决于所应用的碳源。对应分析表明， Gammaproteobacteria_unclassified所属属与醋酸饲喂的 MMC（相对丰度为 38%）和葡萄糖饲喂的 MMC（相对丰度为 76.7%）中的 3-羟基丁酸（HB）合成有关，而弧菌属与葡萄糖饲喂的MMC（相对丰度0.4％）和淀粉饲喂的MMC（相对丰度94.6％）中3-羟基戊酸（HV）的产生醋酸饲喂的MMC不能使用葡萄糖和淀粉作为发酵碳源，显示出局限性具有特定代谢底物的微生物物种。当使用乙酸钠作为发酵碳时，葡萄糖饲喂的MMC产生了最高的PHA细胞含量，为细胞干重的64.2%。葡萄糖喂养的 MMC 对各种碳源表现出广泛的弹性和适应性。采用实际垃圾渗滤液进行葡萄糖饲喂MMC发酵时，获得最大PHA细胞含量为45.5%细胞干重，PHA体积生产率为0.265 g PHA/(L·h)。本研究表明MMC富集阶段应用的碳源对发酵阶段碳的利用具有显着影响。